Coach Chip Kelly’s arrival from the college ranks started talk of an offensive revolution, and previously unheralded QB Nick Foles threw 27 touchdowns and just two interceptions. But this is the NFL, and the question often is: "When, not if, will defensive coordinators catch up and figure out how to unravel (fill in the blank) scheme?" Free-agent RB Darren Sproles is a new toy for Kelly and is one of the league’s most significant matchup problems.

WHO COULD WIN

GIANTS

2013 record: 7-9

Yes, we know that an undefeated preseason means absolutely nothing — but that an exhibition season that produced more questions than answers about an overhauled (supposedly improved) offense means a lot more. The Giants coaching staff has set a high bar for QB Eli Manning, who has completed 58.5 percent of his career passes but is shooting for something near 70 percent this year. Regardless, Manning, 33, must improve after last year’s 18 touchdowns and 27 interceptions.

WHO WON’T WIN

Dallas Cowboys

2013 record: 8-8

Before QB Tony Romo saw his 2013 season cut short because he needed back surgery, he was quite good. He threw 31 touchdowns and 10 interceptions. However, he once again will have to compensate for a beleaguered defense. The Cowboys ranked last in the NFL in total defense last season, then lost LB DeMarcus Ware and DT-DE Jason Hatcher in the offseason and saw LB Sean Lee suffer a season-ending knee injury in OTAs. Not good.

X-FACTOR

Washington QB Robert Griffin III

First, he was electric in leading Washington to the playoffs as a rookie — even heroically fighting through an injured knee that proved to be a lot worse than he let on. Then, he was overbearing and considered a guy whose camp had imposed its will on the organization through an empowering owner. Later, he was borderline insolent and seen as one of the main reasons a possible Hall of Fame coach got himself fired. Now, he might just be tentative. Who’s the true RG3?

NFC WEST

WHO WILL WIN

Seattle Seahawks

2013 record: 13-3

Visions of the Seahawks’ complete domination in Super Bowl XLVIII in East Rutherford are still so fresh, perhaps because there have been very few performances that were so wholly impressive. Every phase of Seattle’s game plan was run to perfection. With even further growth by QB Russell Wilson, it’s impossible to think that Pete Carroll’s bunch won’t make another run deep into January (and possibly February).

WHO COULD WIN

San Francisco 49ers

2013 record: 12-4

The difference between the 49ers and Seahawks, as we saw in the NFC Championship Game, is so incredibly slim. In Jim Harbaugh’s three seasons, the 49ers have reached the NFL’s final four three times and gone to the Super Bowl once. And the motivation of falling short each of those years should be plenty for Harbaugh, QB Colin Kaepernick and a tremendous defense that will have to withstand the early season absences of LBs NaVorro Bowman and Aldon Smith.

WHO WON’T WIN

St. Louis Rams

2013 record: 7-9

If for no other reason than the fact that this is, by far, the most physical and competitive division in football, don’t expect to see the Rams in the postseason. They have quality players on defense — notably, pass-rushing mavens Chris Long (8½ sacks) and Robert Quinn (19 sacks) — but really struggle on the offensive side. That could be said before QB Sam Bradford was lost to another torn ACL during the preseason.

X-FACTOR

Cardinals QB Carson Palmer

Before Kimo van Oelhoffen bent Palmer’s knee the wrong way in a playoff game a few years back, Palmer was on the verge of becoming an elite quarterback. He isn’t elite now, but he is more than capable — and still throws one of the prettiest balls in the league. He has Larry Fitzgerald and Michael Floyd on the outside, but needs to remain upright. He was sacked, hit or hurried a combined 242 times last year — the second most in the NFL.

NFC NORTH

WHO WILL WIN

Green Bay Packers

2013 record: 8-7-1

If QB Aaron Rodgers’ value was ever questioned, just look at the 2013 season. The Packers were 5-2 with Rodgers playing, then went 2-5-1 with him out with a collarbone injury. And then he lifted them into the playoffs in the regular-season finale. Protecting Rodgers is tantamount, and Green Bay must hope the addition of LB Julius Peppers (double-digit sacks in four of past six seasons) will improve a defense that was ranked 25th and gave up the third-most red-zone touchdowns (39) a year ago.

WHO COULD WIN

Detroit Lions

2013 record: 7-9

Three players who should be most excited by the arrival of offensive coordinator Joe Lombardi? QB Matthew Stafford, WR Calvin Johnson and RB Reggie Bush. Stafford and Johnson already are one of the league’s most potent duos, and Lombardi — who worked side-by-side with Saints coach Sean Payton choreographing that record-setting offense — previously worked with the multi-talented Bush. And if rookie TE Eric Ebron can be groomed to be like Jimmy Graham ...

WHO WON’T WIN

Minnesota Vikings

2013 record: 5-10-1

How much more can the Vikings milk out of RB Adrian Peterson? He is 29 and entering his eighth season. After rushing for 2,097 yards in 2012, he "slumped" to 1,266 last season — a further indictment of the lack of a legitimate quarterback. Veteran Matt Cassel is the starter, for now, with rookie QB Teddy Bridgewater waiting. New coach Mike Zimmer is a tremendous leader. He’ll have to be for Minnesota to matter.

X-FACTOR

Bears RB Matt Forte

He had career-highs in rushing yards (1,339) and receiving yards (594), and his 12 touchdowns tied the total he had as a rookie. While the rest of the offense — QB Jay Cutler (career-best 89.2 passer rating in 11 games last year), WRs Brandon Marshall and Alshon Jeffrey (combined 2,716 yards and 19 receiving touchdowns) and TE Martellus Bennett (65 catches, five TDs) — is tremendous, Forte is the true key to coach Marc Trestman’s attack.

NFC SOUTH

WHO WILL WIN

New Orleans Saints

2013 record: 11-5

Perhaps no team will benefit more from the NFL’s emphasis on illegal contact in the secondary than the precision passing game of the Saints. TE Jimmy Graham is a matchup nightmare already and can handle the contact, but the rest of the New Orleans route tree requires space and timing. They should get both, and QB Drew Brees — he has had four of the eight 5,000-yard passing seasons in NFL history — figures to be tough to stop.

WHO COULD WIN

Tampa Bay Buccaneers

2013 record: 4-12

A house cleaning sent former Rutgers coach Greg Schiano on his way and paved the way for Lovie Smith to return to Tampa. Smith rang up nine or more wins five times in nine seasons in Chicago before getting fired after a 10-victory season in 2012. QB Josh McCown assumes the starting role after his 13-TD, one-INT showing last season in Chicago. And new CB Alterraun Verner had five interceptions and 23 passes defended last season with the Titans.

WHO WON’T WIN

Atlanta Falcons

2013 record: 4-12

Matt Ryan is a classic pocket passer. That much has been obvious for quite some time, and allowing him to be sacked 44 times and under pressure on 290 drop-backs overall (he never had been pressured more than 94 times) rendered him helpless throughout a frustrating 2013. So did a flood of injuries to WRs Roddy White and Julio Jones ... and the fact that RB Stephen Jackson is past his prime. There is much work to be done by coach Mike Smith.

X-FACTOR

Panthers WR Kelvin Benjamin

Welcome to the NFL, kid. Not only are you needed to be the No. 1 receiver (steady, if unspectacular, veterans Jason Avant and Jerricho Cotchery are the other options), you must be someone who can stretch the field and make sure QB Cam Newton doesn’t lose his patience weekly. Benjamin was dynamic for Florida State a year ago, and caught the game-winning touchdown in the BCS title game. But this is a big step.